// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef UI_COMPOSITOR_LAYER_DELEGATE_H_
#define UI_COMPOSITOR_LAYER_DELEGATE_H_

#include "base/callback_forward.h"
#include "ui/compositor/compositor_export.h"

namespace gfx {
class Canvas;
class Rect;
}

namespace ui {
class PaintContext;

// A delegate interface implemented by an object that renders to a Layer.
class COMPOSITOR_EXPORT LayerDelegate {
public:
    // Paint content for the layer to the specified context.
    virtual void OnPaintLayer(const PaintContext& context) = 0;

    // A notification that this layer has had a delegated frame swap and
    // will be repainted.
    virtual void OnDelegatedFrameDamage(const gfx::Rect& damage_rect_in_dip) = 0;

    // Called when the layer's device scale factor has changed.
    virtual void OnDeviceScaleFactorChanged(float device_scale_factor) = 0;

    // Invoked prior to the bounds changing. The returned closured is run after
    // the bounds change.
    virtual base::Closure PrepareForLayerBoundsChange() = 0;

protected:
    virtual ~LayerDelegate() { }
};

} // namespace ui

#endif // UI_COMPOSITOR_LAYER_DELEGATE_H_
